Damping of electromechanical oscillations in electric power systems: an approach using partial eigenstructure assignment
Stability; Electrical power systems; Small disturbances; Eigenvalue assignment; Linear feedback control.
In this thesis, a partial eigenstructure assignment methodology is applied to dampen electromechanical oscillations in electrical power systems. The approach is anchored in allocating a small number of undesirable eigenvalues, for example, which are poorly damped, preserving the stable region of the spectrum - the so-called no spillover allocation. The ideal design is carried out using genetic algorithm techniques, and, considering that the order of the system may be higher for a general case, state observers are employed to estimate the states of the system, thus offering a viable implementation in practice. Simulation examples using a system with a synchronous machine connected to an infinite bus and multi-machine systems showed that the presented methodology is efficient in dampening the local and inter-area oscillation modes, quickly stabilizing the system in the event of a small disturbance when compared to the stabilizer of classic power systems. In addition to the traditional design using frequency techniques, genetic algorithms made it possible to obtain the stabilizer parameters and define a region for the partial eigenstructure assignment in order to employ state observers without requiring a great effort from the controller, enabling its implementation for larger systems.